nixos/xserver: Remove with statements

They masked the evaluation error caused by removal of
`defaultSessionFromLegacyOptions` variable
in 6be2bfcc32d5ee203acf3b85354f5028c8bb50eb

nixos/modules/services/x11/desktop-managers/default.nix

···
 { config, lib, pkgs, ... }:
 
-with lib;
-
 let
+  inherit (lib) mkOption types;
 
   xcfg = config.services.xserver;
   cfg = xcfg.desktopManager;
···
       session = mkOption {
         internal = true;
         default = [];
-        example = singleton
+        example = lib.singleton
           { name = "kde";
             bgSupport = true;
             start = "...";
···
           manage = "desktop";
           start = d.start
           # literal newline to ensure d.start's last line is not appended to
-          + optionalString (needBGCond d) ''
+          + lib.optionalString (needBGCond d) ''
 
             if [ -e $HOME/.background-image ]; then
-              ${pkgs.feh}/bin/feh --bg-${cfg.wallpaper.mode} ${optionalString cfg.wallpaper.combineScreens "--no-xinerama"} $HOME/.background-image
+              ${pkgs.feh}/bin/feh --bg-${cfg.wallpaper.mode} ${lib.optionalString cfg.wallpaper.combineScreens "--no-xinerama"} $HOME/.background-image
             fi
           '';
         });

nixos/modules/services/x11/display-managers/default.nix

···
 
 { config, lib, options, pkgs, ... }:
 
-with lib;
-
 let
+  inherit (lib) mkOption types literalExpression optionalString;
 
   cfg = config.services.xserver;
   xorg = pkgs.xorg;
···
       # Import environment variables into the systemd user environment.
       ${optionalString (cfg.displayManager.importedVariables != []) (
         "/run/current-system/systemd/bin/systemctl --user import-environment "
-          + toString (unique cfg.displayManager.importedVariables)
+          + toString (lib.unique cfg.displayManager.importedVariables)
       )}
 
       # Speed up application start by 50-150ms according to
···
     # that do not have upstream session files (those defined using services.{display,desktop,window}Manager.session options).
     services.displayManager.sessionPackages =
       let
-        dms = filter (s: s.manage == "desktop") cfg.displayManager.session;
-        wms = filter (s: s.manage == "window") cfg.displayManager.session;
+        dms = lib.filter (s: s.manage == "desktop") cfg.displayManager.session;
+        wms = lib.filter (s: s.manage == "window") cfg.displayManager.session;
 
         # Script responsible for starting the window manager and the desktop manager.
         xsession = dm: wm: pkgs.writeScript "xsession" ''
···
         '';
       in
         # We will generate every possible pair of WM and DM.
-        concatLists (
+        lib.concatLists (
             lib.mapCartesianProduct
             ({dm, wm}: let
               sessionName = "${dm.name}${optionalString (wm.name != "none") ("+" + wm.name)}";
               script = xsession dm wm;
               desktopNames = if dm ? desktopNames
-                             then concatStringsSep ";" dm.desktopNames
+                             then lib.concatStringsSep ";" dm.desktopNames
                              else sessionName;
             in
-              optional (dm.name != "none" || wm.name != "none")
+              lib.optional (dm.name != "none" || wm.name != "none")
                 (pkgs.writeTextFile {
                   name = "${sessionName}-xsession";
                   destination = "/share/xsessions/${sessionName}.desktop";
···
   };
 
   imports = [
-    (mkRemovedOptionModule [ "services" "xserver" "displayManager" "desktopManagerHandlesLidAndPower" ]
+    (lib.mkRemovedOptionModule [ "services" "xserver" "displayManager" "desktopManagerHandlesLidAndPower" ]
      "The option is no longer necessary because all display managers have already delegated lid management to systemd.")
-    (mkRenamedOptionModule [ "services" "xserver" "displayManager" "job" "logsXsession" ] [ "services" "displayManager" "logToFile" ])
-    (mkRenamedOptionModule [ "services" "xserver" "displayManager" "logToJournal" ] [ "services" "displayManager" "logToJournal" ])
-    (mkRenamedOptionModule [ "services" "xserver" "displayManager" "extraSessionFilesPackages" ] [ "services" "displayManager" "sessionPackages" ])
+    (lib.mkRenamedOptionModule [ "services" "xserver" "displayManager" "job" "logsXsession" ] [ "services" "displayManager" "logToFile" ])
+    (lib.mkRenamedOptionModule [ "services" "xserver" "displayManager" "logToJournal" ] [ "services" "displayManager" "logToJournal" ])
+    (lib.mkRenamedOptionModule [ "services" "xserver" "displayManager" "extraSessionFilesPackages" ] [ "services" "displayManager" "sessionPackages" ])
   ];
 
 }

nixos/modules/services/x11/window-managers/default.nix

···
 { config, lib, ... }:
 
-with lib;
-
 let
+  inherit (lib) mkOption types;
   cfg = config.services.xserver.windowManager;
 in